[Qt-creator] Couple of questions about the design of Qt Creator

[André Pönitz]

On Sun, Sep 10, 2017 at 11:31:58AM +0200, Elvis Stansvik wrote:
> As soon as I hit send, I realized I have a third question:
> 
> 3. Communication Between Plugins:
> 
> There seems to be two main mechanisms through which plugins
> communicate: Either objects that implement shared interfaces are added
> to the plugin manager object pool and picked up by downstream or
> upstream plugins (in the top-down or bottom-up phase of plugin
> initialization, respectively), or a singleton instance is acquired and
> calls made on it.
> 
> Is the former approach used when dependants provide functionality to
> their dependees (which are unknown), and the latter approach used when
> dependees use their dependants (which are known)? Is that the deciding
> factor?

I am not sure there is a strict deciding factor or even policy.
There are certainly historical and personal aspects involved.

The object pool has some systematic quadratic behaviour built-in,
so even if it is still ok, it won't scale arbitrarily. So I am
trying to reduce it's use in well-known cases where one side 
depends on the other anyway, e.g. replace various factories
hat so far ended up in the pool with explicit registration of
their upstream users, and only use the pool where it's flexibility
is really needed.

Andre'